A development of a router has always been closed and monopolistic with a long development cycle and a high development cost. A credibility and security of the router is a hot topic in a field of a router research. Security requirements of users on a router may focus on a sender and a receiver, specifically, data sent by the sender may be correctly transferred, and integrated and accurate data may be received by the receiver. According to the above requirements, irregular behaviors in the router can be divided into four kinds: a behavior of transferring incorrectly, a behavior of transferring maliciously, a behavior of discarding abnormally, and a behavior of tampering with data. How to make a behavior of the router to be credible and secure by detecting and monitoring the above irregular conducts becomes an important problem in a design of the router.